Conventional motor vehicles incorporate foot controls, a typical motor vehicle with an automatic gearbox having accelerator and brake pedals. To permit operation by disabled persons having restricted or no use of their legs, such vehicles may be fitted with hand controls which permit hand operation of the accelerator and brake pedals.
Only a small number of cars specially adapted for disabled drivers have been produced, the majority of drivers using conventional vehicles which have been fitted with hand controls as described above.
Various proposals for such devices are disclosed in the below listed patents and patent application:
U.S. Pat. No. 3,373,628 to L. Lake et al PA1 U.S. Pat. No. 3,442,149 to F. S. Schwendenmann PA1 U.S. Pat. No. 3,472,094 to L. Lake et al PA1 U.S. Pat. No. 4,424,723 to D. A. Gockel PA1 U.S. Pat. No. 4,438,835 to Dowden, deceased et al PA1 U.S. Pat. No. 4,476,954 to Johnson et al. PA1 Canadian Patent No. 1,005,731 to T. Mitro PA1 European Patent Application 0069 090 to G. Venturini PA1 U.K. Patent No. 1,539,880 to E. Aston
From the disclosures contained in these patents and patent application, it is evident that a wide variety of devices has been contemplated. In U.S. Pat. No. 4,476,954 to Johnson et al an electrically actuated control provides for one-handed operation of a motor vehicle through use of a two-axis joystick. The joystick controls a pair of linear actuators and a rotary actuator powered by an electric motor to effect throttle, brake and steering control.
The majority of previously disclosed hand controls are however manually operated and provide direct mechanical links between control handles and levers and the accelerater and brake pedals or controls. In U.S. Pat. No. 3,373,628 to Lake et al, control of a vehicle is achieved by rotation of a steering column mounted handle about an axis parallel to the column, the rotational movement being transferred through a bevel gearbox to cause rotation of a lever, the ends of which are pivotally attached to control rods connected to the accelerator and brake control. In a second embodiment, a steering column mounted handle is rotated about a fulcrum with an axis perpendicular to the column to operate a push rod connected to a lever pivotally mounted further down the steering column. The ends of the lever are pivotally attached to control rods connected to the accelerator and brake pedals.
In U.S. Pat. No. 3,442,149 to Schwendenmann a firewall mounted operating handle is used to operate the brake control by pushing downwardly on the handle and transferring movement through a push rod to the brake pedal, while rotating the handle about a lateral axis operates a system of gears and cranks to depress the accelerator pedal
In U.S. Pat. No. 3,472,094 to Lake et al a steering column mounted, twin handle control is disclosed. The brake pedal of a vehicle fitted with the control is operated by a handle which is pushed downwardly towards the pedals and the accelerator pedal is operated by a second handle which is rotatable about an axis parallel to the steering column.
In U.S. Pat. No. 4,438,835 to Dowden et al a control is disclosed which utilizes push-pull control rods, one for each of the accelerator and brake pedals, the rods being mounted on a support frame secured to the vehicle floor.
In U.K. Patent No. 1,539,880 to Aston, a single handle, steering column mounted control mechanism is disclosed. Rotation of the handle in a plane parallel with the steering wheel operates a Bowden cable linkage to control the accelerator, while movement of the handle in a downward direction parallel to the steering column causes movement of a push rod to operate the brake pedal.
In Canadian Patent No. 1,005,731 to Mitro, a handle in the form of a lever is pivotally attached about a steering column mounting. Push rods extending from the accelerator and brake pedals are pivotally connected to the handle on either side of the mounting, rotation of the handle in one direction resulting in operation of the accelerator pedal, and rotation of the handle in the opposite direction resulting in operation of the brake pedal.
In European Patent Application No. 0 069 090 to Venturini, a hand operated accelerator control is disclosed. The accelerator pedal of a vehicle is connected to a lever system which is attached to a movable sheath which forms the cover of a steering wheel. Twisting the sheath operates levers and push rods to operate the accelerator pedal.
The controls disclosed in the above discussed patents and patent application are connected to the accelerator and brake controls of a vehicle and are also rigidly connected to a fixed point on the vehicle. In the Johnson et al, Lake et al, Aston, Venturini and Mitro disclosures, the devices are adapted for fixing to the steering column of a vehicle. The control disclosed in Schwendenmann is fixed to the firewall of a vehicle, while the Dowden control is fixed to the vehicle floor. Such methods of mounting are preferable for a hand control which is to be used over an extended period, but are inconvenient when a hand control is only desired to be used for a short time. In particular, such mounting will often require extensive and expensive modification to be made to a vehicle to permit the provision of a secure mounting, particularly in modern vehicles, where the steering column is often shrouded in plastic mouldings containing switches, steering locks and other fittings. Due to these difficulties, disabled drivers are often denied access to vehicles, for example for test drives prior to a vehicle purchase, or for renting.
This problem has been appreciated to some extent, and U.S. Pat. No. 4,424,723 to Gockel discloses portable hand control apparatus in which the handle and control rods forming part of the apparatus are free of any operative connection to the motor vehicle, apart from foot pedal clamps. The control rods are pivotally mounted to the foot pedal clamps. The brake control rod is rigidly attached to a brake control handle which slidably receives an end of the accelerator control rod which is provided with a knob element for thumb operation. In use, it would seem most likely that the control rods or handle rests on the operator's knees or lap, or is supported in a raised position by the operator. This would be likely to increase the effort required to operate the vehicle.